I think having daily injections would not be a good strategy. I think, depending on efficacy of drug, having a slow release, similar to how some female birth control works, or having a pill, that would be the best option. And if the drug is binding to the sperm, a vaginal jelly is an alternative.
If it became a pill, how long before sex would men have to take it? Do you think this is something that men could take immediately before sex and be protected?
It'd be unlikely they could take a pill that could kill all the live sperm in the epididymis [the tube where sperm live before ejaculation]. I think it'd be kind of like pill in women, they'd have to be on the pill for a month or so before it has an effect. I think one of the best pills out there would be something taken once a week, so you could take it and it would last a while and could maybe reduce any other effects of the drug.
Obviously it's early, but do you see this as being a low cost solution?
I think to be an effective pill you need the costs low, there's a few ways to do that. I don't know if the answer is subsidies from government, but I think you need to have the costs as low as possible for men to want to use it.
Jason Koebler is a science and technology reporter for U.S. News & World Report. You can follow him on Twitter or reach him at email@example.com